A booster circuit configured with a three-terminal comb teeth actuator manufactured through the MEMS technology is known in the related art (see patent literature 1). The three-terminal comb teeth actuator described in patent literature 1, comprises a first comb teeth actuator that includes a first comb teeth electrode and a second comb teeth electrode engaged with the first comb teeth electrode via a specific gap and a second comb teeth actuator that includes a third comb teeth electrode and a fourth comb teeth electrode engaged with the third comb teeth electrode via a specific gap. In this three terminal comb teeth actuator, the second comb teeth electrode and the third comb teeth electrode are formed as an integrated unit so as to achieve equal extents of displacement and an output is extracted from one of the comb teeth electrodes.
To describe the booster circuit disclosed in patent literature 1 in more specific terms, it includes two electrostatic actuators, an input-side electrostatic comb teeth actuator and an output-side electrostatic comb teeth actuator manufactured through the MEMS technology. The movable comb teeth electrodes in the two electrostatic actuators are made to interlock with each other through a mechanical link, and a DC voltage is separately applied to the output-side electrostatic comb teeth actuator or an electric field is generated via an electret for the output-side electrostatic comb teeth actuator (see FIG. 1 and FIG. 2 in patent literature 1). The two electrostatic actuators are placed in an environment achieving a high degree of vacuum (vacuum sealing of the movable comb teeth electrodes) and an AC input is applied toward the input-side electrostatic actuator (or self-excited oscillation is induced by forming a feedback circuit). In this situation, as the input-side electrostatic actuator oscillates, the output-side electrostatic actuator also oscillates, which induces an electric charge through electrostatic induction and ultimately provides a voltage boosted to a level equal to or higher than the input voltage. The output voltage thus obtained, which is an AC voltage, undergoes rectification in a circuit disposed at a subsequent stage so as to obtain a boosted DC voltage.